1. Field of the Invention
The invention relates to a vehicle wheel with a tire detachably mounted thereon. The tire has a body which is torus-shaped in cross-section and has an approximately cylindrically bearing surface and two side walls that run radially. The tire walls have a tire seat located at their ends which points toward the rim and is reinforced by non-extendable core pullers which attach the pneumatic tire between radially outwardly extending terminal clinches of the wheel. The invention further relates in particular to an encircling disk-type ring that is arranged on one of the clinches to extend the clinch in the radial direction.
2. Discussion of the Prior Art
In vehicle wheels, the pneumatic tire is currently considered the structural element which must transmit all operationally-conditioned forces from the vehicle to the street and vice versa. The efforts of manufacturers are therefore concentrated on optimizing the pneumatic tire, especially in respect to its usage characteristics, i.e., handling, rolling resistance, friction force transmission between the tire and the road, and comfort and wear, so far as possible without sacrificing the advantages and qualities already achieved.
Today, vehicle wheels of this type are known and customary in vehicles of all sorts, especially in motor vehicles and their trailers.
Recent development research has been concentrated on making improvements in the pneumatic tire, especially in the belts inserted therein. However, this concentration of development efforts in the area of belts or tread strips of known pneumatic tires used today fails to take into account the fact that the structurally reinforced "tire beads," which are radially located above the tire seating at approximately the level of the casing covers in the side walls, also contribute significantly to the rolling resistance of the tire, due to the lateral bulges brought on by the circumferential disturbance on the tire contact area.
This problem cannot be corrected or influenced by improvements in the belt. In particular, too little attention has been paid until now to the fact that the tire is only one part of the wheel system, the other part of which is the rim on which the tire is mounted.
In order to improve the usage characteristics of pneumatic tires, it is thus not sufficient to undertake modifications only in the area of the belt. Instead, the side wall areas of the pneumatic tire with the problematic tire beads and the rim must also be part of the solution.
The vehicle tire would thus need to have a rim which not only serves as a mount for the pneumatic tire, but also performs precisely defined support functions for the mounted tire.
In order to meet the requirements mentioned above, a vehicle wheel with tire has been proposed with a rotatably-mounted rim with terminal clinches which extend radially outward, in which at least one of the clinches is of greater radial length.
The elongation extends at least into approximately the central area of the side wall in question of the pneumatic tire and runs, in its radial extension, more steeply--i.e., is inclined more to the inside--than the natural bending contour of the tire side wall, which is under internal pressure. Preferably, the lengthened clinch is located on the side of the wheel which faces the vehicle. This proposal has the disadvantage that a wheel manufactured in this manner deviates from the norm, so that retrofitting vehicles already approved would entail an exchange of wheels involving corresponding expense. In addition, mounting the pneumatic tire is made more difficult, because in many wheel designs the clinch located on the vehicle exterior has a larger outer diameter than the interior clinch. In no case is it possible to draw the tire on over the lengthened clinch. A further disadvantage is that in order to make adjustments to meet different requirements related to steering behavior and driving comport, it is necessary to manufacture a new wheel, since the length of the elongation as well as the inclination of the lengthened clinch to the wheel axis have a decisive influence on driving behavior.
In an alternative proposal, an encircling disk-type metal ring is clamped or shrunk on the clinch in order to lengthen the clinch. Mounting such a ring is very expensive, since doing so requires heating the ring and cooling the rim. In addition, there is a danger that the shrink joint will be loosened by the elastic flexing of the wheel. This is also true for the clamp connection. A further disadvantage is that the amount of positive-locking support for the ring on the clinch is sharply limited by the small mounting-conditioned diameter difference attainable between the inner diameter of the ring and the outer diameter of the clinch.